Intensity speckle MR elastography
نویسندگان
چکیده
Introduction: Magnetic resonance elastography (MRE) allows the measurement of the mechanical properties of living tissue by combining shear waves and motion sensitive MRI [1]. In classical MRE, shear wave images are evaluated using an appropriate wave inversion technique for calculating an estimate of the spatial distribution of the shear modulus within the region of interest [2]. Problem: Wave inversion is mathematically ill-posed and thus error prone due to unknown boundary conditions and discrete and noisy data. For this reason, recent developments aimed to deduce structure related information from MRE wave images without the need of wave inversion [3, 4]. Objective: In this paper we present an analysis of shear wave scattering by means of a statistical analysis of the shear wave intensity. From this analysis a single dimensionless fit parameter is available. This parameter provides a measure for the length scale on which shear wave scattering occurs. Hence, this parameter is sensitive to the mechanical structure of tissue on a mesoscopic level which is otherwise inaccessible by non-invasive medical imaging modalities. The novel method is demonstrated by phantom experiments and in vivo MRE of the human brain.
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